The present invention relates to a system for controlling an electromagnetic clutch for an infinitely variable belt-drive transmission.
An automobile provided with an infinitely variable belt-drive transmission with an electromagnetic clutch is known. The infinitely variable belt-drive transmission is controlled by a control system to provide various operational ranges such as a drive range (D-range), high engine speed drive range (Ds-range), reverse range (R-range), neutral range (N-range), and parking range (P-range). When the Ds range is selected during the drive range driving, the transmission ratio of the transmission is raised, so that engine braking effect is brought about. On the other hand, in the infinitely variable belt-drive transmission, the static friction torque in the belt and pulley device at starting of the automobile is large. Accordingly, it is necessary to deal with the problem of the large static friction torque. Further, inconsistent requirements such as increasing the clutch torque at the engagement of the clutch and improvement of electric power consumption should be fulfilled.